Scilab Function
Last update : 12/1/2004

arma2p - extract polynomial matrices from ar representation

### Calling Sequence

  `[A,B,D]=arma2p(ar)`

### Parameters

- `A,B,D`: three polynomial matrices
- `ar`: Scilab 'ar' tlist for arma storage (see `armac`).

### Description

this function extract polynomial matrices `(A,B,D)` from an armax description.

### Examples

    a=[1,-2.851,2.717,-0.865].*.eye(2,2)
    b=[0,1,1,1].*.[1;1];
    d=[1,0.7,0.2].*.eye(2,2);
    sig=eye(2,2);
    ar=armac(a,b,d,2,1,sig)
    // extract polynomial matrices from ar representation
    [A,B,D]=arma2p(ar);

### See Also

`arma`, `armax`, `armax1`, `arsimul`, `armac`,